One of the most persistent and troublesome problems arising during modern fabric laundering operations is the tendency of some colored fabrics to release dye into the laundering solutions. The dye is then transferred onto other fabrics being washed therewith.
One way of overcoming this problem would be to bleach the fugitive dyes washed out of dyed fabrics before they have the opportunity to become attached to other articles in the wash.
Suspended or solubilized dyes can to some degree be oxidized in solution by employing known bleaching agents.
GB 2 101 167 describes a stable liquid bleaching composition containing a hydrogen peroxide precursor which is activated to yield hydrogen peroxide on dilution.
However, it is important at the same time not to bleach the dyes actually remaining on the fabrics, that is, not to cause color damage.
U.S. Pat. No. 4,077,768 describes a process for inhibiting dye transfer by the use of an oxidizing bleaching agent together with catalytic compounds such as iron porphins.
U.S. patent application Ser. No. 07/421,414 now abandoned describes peroxidases and oxidases utilized for the oxidation of organic or inorganic substances, including coloured substances. A dye transfer inhibiting composition comprising an enzymatic system capable of generating hydrogen peroxide and iron catalysts has been disclosed in copending EP Patent Application 91202655.6 filed Oct. 9, 1991.
EP 424 398-A describes a detergent additive capable of exerting a bleaching effect comprising a peroxidase. The additive further comprises one or more enzymes, particularly a lipase, protease, amylase or a cellulase.
EP-A-350 098 discloses a C14CMC-method which defines a cellulase selection criteria relevant for detergent application. A minimum of 10% removal of immobilized radioactive labelled carboxymethylcellulose according to the CMC-method at 25.times.10.sup.-6 % by weight of the cellulase protein in the test solution has been found to provide high active cellulase.
A preferred group of cellulase falling under the high activity definition according to the present invention has been disclosed in copending Danish Patent Application No. 1159/90 filed May 5, 1990. There is disclosed a cellulase preparation consisting essentially of a homogeneous endoglucanase component which is immunoreactive with a monoclonal antibody raised against a partially purified=43 kD cellulase derived from Humicola insolens DM1800.
It has now been surprisingly found that the efficiency of peroxidases in terms of dye transfer inhibition, is considerably enhanced by using said high activity cellulase and more in particular the specific cellulase preparation disclosed in copending Danish Patent Application No. 1159/90. It is therefore an object of the present invention to provide dye transfer inhibiting compositions which exhibit optimum dye transfer in wash liquids by using said high activity cellulase and peroxidase.
According to one embodiment of this invention a dye transfer inhibiting composition is provided which comprises a cost-effective cellulase preparation, e.g. by employing recombinant DNA techniques.
According to another embodiment of this invention a process is also provided for laundering operations involving colored fabrics.